My idea would be that the basic kernel would have a lot of vulnerabilities, this would encouraged players to build their own kernel from the source already available so they don't have to start from scratch

This was actually precisely the idea. The initial kernel source code was going to be available to all players in-game.

I was going to release the the occasional update which would patch a few of the vulnerabilities. These updates will be available at an in-game store, so players will need to fork out credits to upgrade.

The initial kernel will allow remote shelling by default, and have a few other networking ports widely open.

Special in-game hosts will have a bit more of a hardened kernel, and it's patches will not be available. These are for the banking, ranking, mail, DNS, and in-game help/documentation servers. I'd rather these special hosts not be attacked too soon in the lifespan of the game. If some of these go down, then newbies will be entirely lost, and might even give up hope in playing.

KERNEL sourc code ingameccatlett2000Aug. 12, 2016, 1:25 p.m.

Well, if I was to compromise a special server (Especially banking), I definitely wouldn't show my hand by doing something stupid like taking it offline :). But yeah, that might be a good idea.